Multiple key locking system



March 6, 1951 c. J. FINKE ET AL 2,544,305

MULTIPLE KEY LOCKING SYSTEM Filed July 28, 1948 3 Their A'ttorneg.

Patented Mar. 6, 1951 y 25.44.305; l MULTIPLET`KEY' LOCKmG. SYSTEM' Qhristian J..Finkc, Drexel .HilL and` Miguel A- Guzmalll Philadelphia, Pa., asSignors to General .Electric Gompan York y a. corporation@ New application July as, 1era-.scheine einer comme' (o1. vor-assi The .inventlorlv relates to mnltiplerkey. locking; systems. particularly intcrlockinglsystems involving-.a plurality of locker.

Qne; .object is i to. provide. an` improved doubleend` doubleflrevtoriaf o t. cylinder. looking... device thatmav be4 used with advantage. switchgear satetyinterlocking.sgstenis .or other ,similar .serve ice-where it is. desired'. to..k enforce. predetermined... locking. operations bv means 'of'. two separately. and.oppositelvremovablekeys.

Another object.. to.. .providey an. imrovedl double-key cylinderplocking. device with. angel-arly' related. -ontwardl open twvreceiving.' slots. :and detente` at. .opposite endsthereof so. as. to enable. 011e: Qf the keys. Gofhecome detached for unlocking. another: lock onlyvrhilethe douille-key .lock-V ingfr device isv locked tothe'other key thereof Thus in. accordancewith one .form ot the inventionone of the keys mov be permanently. iixcd sojthat a movable. interlocking .member or door. or. the like carrying theedonblerkev .lock bodymust always be locked to. therelatively fixed key ina.. predetermined position. beforethe other. key can. be detached.. for unlocking another lock.,. Another `Object. to provider an. doublegkey cylinder. lock having. cooperating. sets. o'i'detents. relativen,7 .angularly .displaced .soA that Ieach key locks the cylinder in a different anfghlar positionandislocked in. the .cylinder when the other kevis removed..

Further objects and advantages-of the invert tient/ill appear. in.. theY following.. description.. oi the accompanying drawing. .and its scoper will .be pointed out in the appended, clairris.

In the. drawings..Eig.;` l.v is a; perspective view partly in section ofia. typical switcheear interlock..

embodyingthe .double V-kezvs `sequential lockingirnf provenienti ortho presentlinvention with thefparts shown in; the. loclsedinterloclrine@ position-f. and. W i1 one of: .the here.. ofil thezdoubleeend. double:

ken' locking.' device. removed; Fig... similar. ,perspective view` olf'tne` interlockingmechanism- 'sl'xjovfriinFial 1" withthe movable interlock,meme-.-I

ber out of. its. interlocking positionso that theremovablekey shown .ilrFigf l.. is# locked'inthe lock; Figs. 3 and arrecife esectionalviewsfoi the. .iniproyedrloulole-.key double tumbler-.cylinder vlock rlockina member -e T l safraginentary viewgofsasliahtly .rnodiiiod unproved lgs hedonhle-endrkev l r giving.. cylinder in the: doler-ent angular.posi-.T-

tions.' that permit removal of the correspondirlgr f.

formo?. doiible-endtnrnbler cylinder .ConstrpotionY and lil-ig.y 'I' shows. a further planar aligned hey and. tumbler' modiiication. of; the. .double-.end

'able interlocking, member, I I interlocking en..-

gagement with the hexagonal ends of the. ro. tatable high .and low speeddriving. shafts l2` .and

Iofi an .ordinary forrnoi circuit breaker elevatin g or.. positionrchangine mechanism indicated.

generally by the reference .character le So as to. positively prevent rotation of either shaft when the interlocking member Il isin its interlocking position as shown- To accomplish this purpose.. y With minimum strain ontheloolrr Illtheinterlockfing member ll is provided with `an hexagonal Socketopening |16 forreceiving thehexagonalend of .thelow speedshaft I3 thereinancl with a cirular opening l1 for receivingthe. .hexagonal end oi the high .soeed shaft l2: thereinsoas tomechanif cally block the shaft I3. against rotation` and.,

thereby` preventoperation oi the elevating mechanism lll until the interlock member Il is removed.,

The improvedlocking device l (l is providedwithv a blocker body 2li. having theusual opposite iiattened sidesv 2l for mounting. the lock i-n a correa.

spondingly shaped.. opening formed in the inter-- lock` member Il or the like and- With the usual threaded sides 2.2 for threadedJ engagement with,

therclamoin'g nut- 23ltoclamp the interlock member. Lllbetxveen the flangednose. 24 of the block Zit-.and .the 4clarnp''-ng nut., 2.3,.`

' As indicated moreclearly. inthe sectional` views..

ofjEi'gsL ,3 vand. .fl .the lockv lllis. provided with a double tumblerv cylinder 26 that is rotatably.

mounted in .the block or body an and. is heid against axial movement in. the body 2n, by a` pin.,

3 I. that. engages with 4 a corresponding channel or.

groove 32 extending circumferentially around tlieleylinder l2,6. vIhe.rotatablecylinder 2t s'bnrovided-with `ar.,lg-ularlv displaced outwardly openkeyereceiving Slots.. 21 and :8in the opposite- .ends

thereof for the corresponding removable Kevf r2.9 1 and .therelatvely ixed key `s0-.so as to require re. moval andY insertion of' thel two keys in. oppositev axial directions..

The removal .key .29 which also. .is-used .for nnlockng. another lock. has rcgiste ring` engagement aisetoifcvliniler tornblersiicarried in suit-1,

locking engagement with the cylinder bores of.

the corresponding tumbler 33 when the key 29 is withdrawn from slot 21 for unlocking the other lock while at the same time locking cylinder 26 against rotation from the angular position shown in Figs. 1 and 3.

In accordance with the present invention the key-receiving slot 28 at the opposite end of the cylinder 26 is angularly displaced from the keyreceiving slot 21 and this is also true of the set of cylinder tumblers 31 that are carried in suitable bores formed in radial alignmentwith the key slot 28 for cooperation with the row of body tumblers 38 carried in suitable bores formed in the body 28. Furthermore, as shown in both Figs. 3.

and 4 the row of body tumblers 38 is formed in alignment with the row of body tumblers 34 in the body while the cylinder tumblers 31 are angularly displaced from the tumblers 33 in the cylinder, this displacement being 90 in the preferred form of lock illustrated. When key 30 is withdrawn from slot 28 in the cylinder 26 or vice versa in case key 30 is relativelyxed, the row of block tumblers 38 are forced upwardly by the springs 39 so as to positively lock the cylinder 26 against rotation from the angular position shown in Fig. 4 thereby effectively preventing removal of the key 29 from slot 21 at the opposite end of the cylinder.

Thus, whenever key 20 is insertedin slot 21 to rotate cylinder 26 to the angular position vshown in Fig. 4 wherein key 30 can be removed from slot 28, then the key 29 becomes locked in the cylinder by the engagement of tumblers 33 therewith and vice versa. Hence the key 29 can be removed and used for unlocking anotherlockonly when the lock body 28 is locked to the key 30 as shown ,in Figs. 1 and 3 but is irremovably held inthe slot 21 when the cylinder 26 is turned to a different angular position such as shown in Fig. 4 wherein the lock body 28 can be released from the `iixed key 38.

If desired, the modified cylinder construction illustrated in Fig. 6 may be used in the double-key double tumbler form of lock. As shown in Fig. 6,.

a pair of rotatable cylinders `26a and 2Gb are provided with interlocking dove-tailed ends to insure rotation of both parts in unison in the body 2 9 of.

the lock. In this case each one of the cylinder parts is held against axial movement in the body by means of separate pins 3Ia and 3Ib which cooperate with circumferentialgrooves in substantially the same way as previously described. Each of the cylinderparts 26a and 26h is provided with a key slot and a set of cylinder bores that are angularly displaced in the same way as previously described.

With the improved angularly displaced doublekey lock construction of the present invention, it will be evident that as shown in Fig. 1 the interlocking member Il is locked in its interlocking position by the engagement of the fixed key 39 with the set of tumblers 31 in the cylinder 26 and the cylinder 26 is locked against rotation by engagement of the row of tumblers 34 with the bores formed in the cylinder. As shown the relatively fixed-key 38 is rotatably attached to the Wall I5 of the elevating mechanism I4 by means of a headed swivel member 4| that extends through the wall I5 with the key 30 secured thereto by the pin 42. Thus the relatively fixed key- 30 can rotate inthe wall I5 about the axis ofthe headed swivel, member 4I but cannot be removed therefrom. l

In order to remove the interlocking member II from its interlocking position as shown in Fig. 1

'so as to permit rotation of shaft I3 of the breaker elevating mechanism I4, it is necessary first to insert the key 29 in the slot 21 and thereby align the cooperating tumblers 33 and 34 `to permit rotation of cylinder 26 so as to bring slot 28 and tumbler set 31 at the opposite end of the cylinder into alignment with the row of block tumblers 38. Thereupon the interlocking member II may be bodily removed from its engagement with the shafts `4I2 and I3 with the locking device I8 carried along therewith out'of engagement with the fixed key 30 and key 29 non-removable from the slot 21 as shown in Fig. 2. Consequently, the f only way that key 29 can be made accessible for' unlocking another lock such, for example, as

" shown in Fig. 5 is to replace the interlock member II intointerlocking engagement with the shafts,i I2 and I3, thereby inserting key 38 in slot 23 and aligning the tumblers 31 and 38 so as to permit vrotation of the cylinder 26 by means of the key for unlocking the lock 45 which is fastened tothe solenoid mechanism 49 of the breakerf41. The

solenoid mechanism` 49 is the means foropening, and closing the contacts of breaker 41. Only' when the breaker 41 which as schematicallyv shown in the interlocking system of Fig. 5 is raised by the elevating mechanism I4 into. engagement with disconnect 48, can the breaker contactsbe closed. To remove the breaker from, the housing' the iirst thing is to lockthe breaker open, with key 29 in lock 45, remove key 29 and place in the interlocking member II, unlock and remove thei interlocking vmember I I from the shafts I2 and I3. The key 29 cannot now be removed from the interlock II, and now by means of the elevating mechanism I4 the breaker can be. lowered for removal from the housing.

In this way the improved locking device of the present invention eiectively insures that the cir-A cuit breaker 41 can be closed by operation of the solenoid 49 only when the interlockingrnember I I -is Vlocked in its interlocking position to prevent operation of the elevating mechanism I4.. Con-. versely the interlocking member I I can be r e moved only when the key 29 is inserted in slot 21 after removal from thelock 4 5. with this lockl locked in position to prevent operation of theA solenoid 49 and at the saine time, effectively insure no operation of the breaker. i

A It should be understood however that the im proved locking device of thepresent invention is not limited in its application to the circuit breaker interlocking systemillustrated schematicallydn,

Figs. 1 and 5, but may be applied to other forms. of interlocking members or to doors or the like in any service where it is a desire to enforce a pretermined sequence of locking operations.

Furthermore, it will be understood luy-those skilled in the art that many of the advantages of the present invention can be obtained when the key slots 21 and' 28, together with the cylinder tumblers 33 and 31, are formed in planar alignment in cylinder 26 and the row of body tumblers 34 is angularly displaced 90 from the row of body tumblers 38 in the lock body 20. Thus with either the relative angularly displaced detent construction illustrated in the drawings or the alternative relative angularly displaced detent construction just described, the double-key lock has a rotatable cylinder provided with a key-receiving slot at each end thereof and cooperating relatively angularly-displaced tumblers for locking the cylinder in different angular positions with a corresponding one of the keys locked therein. Furthermore, each key locks the cylinder in a separate angular position and is locked in the cylinder when the other key is removed.

In the modiiied form of the invention shown in Fig. 7, the essential parts of the double key lock Il) are substantially the same as previously described so as to require removal and insertion of the two keys in opposite axial directions except that the outwardly open key slots 21 and 28 are formed in planar alignment in the opposite ends of the rotatable cylinder 26l and the two sets of cylinder detents 33 and 31 as well as the cooperating sets of body detents 34 and 39 also are formed in planar alignment in the cylinder 26 and in the lock body 29. Furthermore, an operating cam 60 is xedly secured to the projecting end 26 of the rotatable cylinder 26 so as to operate a suitable interlocking device such, for example, as the pivotedly mounted switch member 6 I. As shown, the switch member 6l is biased to the open position by the compression spring 62 so as to normally disengage the cooperating switch contact 63 and rest against the stop 64 when the lock l0 is in its unlocked position in which it is shown in Fig. '1.

Thus, in order to close the interlocking switch 6| into engagement with contact 63 so as to complete an electric interlocking circuit, both of the keys `29 and 30 must be inserted into their respective slots at the opposite ends of the cylinder 26 the cylinder when the other key is before the cooperating sets of cylinder and body detents 33, 34 and 31, 39 are brought into aligngk ment to permit free rotation of the cylinder 26 in the barrel 20 so as to rotate cam 60 to close the interlock switch. Hence, if key 29 is in the possession of one person and key 30 in the possession of another person, it is necessary that both persons insert their respective key in the lock before the interlocking switch can be closed and opened by operation of either key. Furthermore, when the interlocking switch is closed, both keys are locked in the lock and it is only when the interlocking switch is open that either key can be removed to unlock another lock.

It will be evident to those skilled in the art that many of the advantages of the present invention can be obtained when the cylinder 26 is flxedly mounted and the lock body 20 arranged to be rotated on the cylinder along with an interlocking cam member or the like only when the two keys 29 and 30 are each inserted in their respective slots in the opposite ends of the cylinder. In this case both keys become locked in the lock when the body 20 is rotated so as to angularly displace the two sets of body tumblers 34 and 39 from the cooperating sets of cylinder tumblers 33 and 31. Consequently, neither key can be removed for unlocking another lock unless the lock body 20 together with its interlocking member carried thereby is in a predetermined interlocking position wherein the body and cylinder tumblers are in planar alignment.

What we claim as new and desired to secure by Letters Patent of the United States is:

1. A double-key sequential locking device having a pair of separately removable keys and a rotatable cylinder provided with an outwardly open key-receiving slot in each end thereof to require removal and insertion of the two keys in opposite axial directions and cooperating relatively angularly-displaced tumblers for locking the cylinder in different angular positions with a corresponding one of the keys locked therein when the other key is removed.

2. A double-key sequential locking device having a pair of separately removable keys and a body provided with tumblers, a cylinder rotatably mounted in the body and provided with an outwardly open key-receiving slot to require removal and insertion of the two keys in opposite axial directions and cooperating tumblers at each end thereof having a relative angular displacement with respect to the body tumblers whereby each key upon removal locks the cylinder in a separate angular position and upon insertion is locked in removed.

3. A double-key sequential locking device having separately removable keys and comprising a pair of interconnected tumbler locks in opposing alignment and having a 'common body and an interconnected pair of cylinders rotatable as a coaxial unit in the body and each provided with an outwardly open key-receiving slot to require removal and insertion of the two keys in opposite axial directions, and cooperating relatively angularly displaced tumblers in the body and cylinder whereby each key upon removal locks the cylinders in a separate angular position and upon nsertion is locked in the corresponding cylinder when the other key is removed.

4. A double-key locking device having a pair of separately removable keys and comprising a tumbler lock body having two rows of body tumbler bores formed in alignment therein, a cylinder rotatably mounted in the body and provided with angularly displaced outwardly open key-receiving slots at the opposite ends thereof in opposite moval and insertion of the two keys in opposite axial directions and angularly` displaced tumbler bores formed therein in cooperating axial alignment with the body bores, and cooperating tumbler sets mounted in the body and cylinder bores whereby each key upon removal locks the cylinder in a different angular position and upon insertion is locked in the cylinder when the other key is removed.

CHRISTIAN J. FINKE. MIGUEL A. GUZMAN.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,409,094 Greenison Mar. '1, 1922 2,126,333 Kirk Aug. 9, 1938 2,220,786 Grainger Nov. 5, 1940 2,336,936 Johnson Dec. 14, 1943 FOREIGN PATENTS Number Country Date ,329,162 Italy Sept. 2 1935 Certificate of Correction Patent No. 2,544,305 March 6, 1951 CHRISTIAN J. FINKE ET AL.

It is hereby eertied that error appears in the printed specification of the above numbered patent requiring correction as follows:

Column 6, line 48, strike out the Words in opposite and insert instead to require reand that the said Letters Patent should be read as corrected above, so that the same may conform to the record of the casein the Patent Oiice.

Signed and sealed this 19th day of June, A. D. 1951.

[SEAL] THOMAS F. MURPHY,

Assistant Commissioner of Patents., 

